diff --git a/ChangeLog b/ChangeLog
index 718560fbf3..5bda2daaac 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed May 16 15:43:10 2012  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* ext/extmk.rb (exts.mk): use double quotes instead of single quotes
+	  for commandline because it's not recognized as quotes on Windows.
+
 Wed May 16 15:15:55 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* configure.in (LD): enclose with single qoutes but not double quotes
diff --git a/ext/extmk.rb b/ext/extmk.rb
index c8ff664b33..3f1f1aca0a 100755
--- a/ext/extmk.rb
+++ b/ext/extmk.rb
@@ -649,7 +649,7 @@ if $configure_only and $command_output
     mf.puts
     mf.puts "#{rubies.join(' ')}: $(extensions:/.=/#{$force_static ? 'static' : 'all'})"
     rubies.each do |tgt|
-      mf.puts "#{tgt}:\n\t$(Q)$(MAKE) $(MFLAGS) EXTOBJS='$(EXTOBJS)' EXTLIBS='$(EXTLIBS)' $@"
+      mf.puts "#{tgt}:\n\t$(Q)$(MAKE) $(MFLAGS) EXTOBJS=\"$(EXTOBJS)\" EXTLIBS=\"$(EXTLIBS)\" $@"
     end
     mf.puts "ext/extinit.#{$OBJEXT}:\n\t$(Q)$(MAKE) $(MFLAGS) V=$(V) $@"
     mf.puts